Analysis of Smart Grids Technologies

The increasing integration of distributed generation (DG) in the electric power supply systems initiates new supply assignments and load flows in the electric distribution systems. In order to guarantee the sustainability of supply, the traditional electric distribution systems must be further developed towards a “Smart Grid”.

For the term “Smart Grid” currently there are various definitions and the term was for long time only a future vision with limited practical relevance. However, the upcoming reconstruction of the distribution systems requires the implementation of the new technologies. A quantitative cost/benefit analysis of both the traditional grid extension and the modern Smart Grids Technologies is prerequisite for the economical implementation and consequently the success of the “Energiewende”.

In order to quantify the utilization of the Smart Grids Technologies, the chair of ES+EM develops a new metrics named “Smart Grid Metric”. It is possible to quantifiably determine and compare the achieving degree of the targets. The Smart Grid Metric provides the technical and economic Base for the implementation of a “Smart Grid”.

• The "Smartness" definition of a distribution grid and clear distinction between the targets and measures;
• Calibration and review of the metric by application on the real and synthetic distribution systems under the consideration of different supply tasks;
• Development of the visual tool to present the "Smartness" and test on the real grids;
• Cost/benefit analysis according to the targets and measures.

• The Targets-Measures Table (see Table 1) completes the definition and separates the targets and the measures. Then it is possible to find the achievements of these targets;
• Simulation of various measures by means of synthetic test grids with normal and also extreme characteristics (Fig. 2 presents an example);
• Quantification of "x" und "(x)" in the Targets-Measures Table concerning cost/benefit aspect;
• Spider diagram is used to display the "Smartness" of the distribution systems (see Fig. 1).

• Definition of the "Smartness" for a distribution grid: An electric distribution grid is smarter than a reference grid if it meets a given set of grid performance targets better.
• Targets-Measures Table

M. Sc. Han Rui

Arnold, M.; Rui H.; Wellßow, W. H.: "An Approach to Smart Grid Metrics", IEEE PES Innovative Smart Grid Technologies (ISGT) Europe 2011, Manchester, United Kingdom, 2011

Arnold, M.; Rui, H.; Wellßow, W. H.: Die Leistungsfähigkeit von Stromnetzen messbar machen: "Smart Grid Metrik". VDI/VDE TechnikForum, 1/2012

Rui, H.; Arnold, M.; Wellssow, W. H.: Synthetic MV-Grids for the Assessment of Smart Grid Techniques; IEEE PES Innovative Smart Grid Technologies (ISGT) Europe, Oktober 2012, Berlin

Arnold, M.; Rui, H.; Wellßow, W. H.: Modellierung synthetischer Mittelspannungsnetze zur Simulation der Effizienz von Smart-Grid-Technologien; VDE-Kongress, November 2012, Stuttgart